# -*- coding: utf-8 -*-
# Part of Odoo. See LICENSE file for full copyright and licensing details.

import itertools
import time

from odoo import api, fields, models
from odoo.tools.sql import SQL


class ProductProduct(models.Model):
    _inherit = "product.product"

    date_from = fields.Date(compute='_compute_product_margin_fields_values', string='Margin Date From')
    date_to = fields.Date(compute='_compute_product_margin_fields_values', string='Margin Date To')
    invoice_state = fields.Selection(compute='_compute_product_margin_fields_values',
        selection=[
            ('paid', 'Paid'),
            ('open_paid', 'Open and Paid'),
            ('draft_open_paid', 'Draft, Open and Paid')
        ], string='Invoice State', readonly=True)
    sale_avg_price = fields.Float(compute='_compute_product_margin_fields_values', string='Avg. Sale Unit Price',
        help="Avg. Price in Customer Invoices.")
    purchase_avg_price = fields.Float(compute='_compute_product_margin_fields_values', string='Avg. Purchase Unit Price',
        help="Avg. Price in Vendor Bills")
    sale_num_invoiced = fields.Float(compute='_compute_product_margin_fields_values', string='# Invoiced in Sale',
        help="Sum of Quantity in Customer Invoices")
    purchase_num_invoiced = fields.Float(compute='_compute_product_margin_fields_values', string='# Invoiced in Purchase',
        help="Sum of Quantity in Vendor Bills")
    sales_gap = fields.Float(compute='_compute_product_margin_fields_values', string='Sales Gap',
        help="Expected Sale - Turn Over")
    purchase_gap = fields.Float(compute='_compute_product_margin_fields_values', string='Purchase Gap',
        help="Normal Cost - Total Cost")
    turnover = fields.Float(compute='_compute_product_margin_fields_values', string='Turnover',
        help="Sum of Multiplication of Invoice price and quantity of Customer Invoices")
    total_cost = fields.Float(compute='_compute_product_margin_fields_values', string='Total Cost',
        help="Sum of Multiplication of Invoice price and quantity of Vendor Bills ")
    sale_expected = fields.Float(compute='_compute_product_margin_fields_values', string='Expected Sale',
        help="Sum of Multiplication of Sale Catalog price and quantity of Customer Invoices")
    normal_cost = fields.Float(compute='_compute_product_margin_fields_values', string='Normal Cost',
        help="Sum of Multiplication of Cost price and quantity of Vendor Bills")
    total_margin = fields.Float(compute='_compute_product_margin_fields_values', string='Total Margin',
        help="Turnover - Total cost")
    expected_margin = fields.Float(compute='_compute_product_margin_fields_values', string='Expected Margin',
        help="Expected Sale - Normal Cost")
    total_margin_rate = fields.Float(compute='_compute_product_margin_fields_values', string='Total Margin Rate(%)',
        help="Total margin * 100 / Turnover")
    expected_margin_rate = fields.Float(compute='_compute_product_margin_fields_values', string='Expected Margin (%)',
        help="Expected margin * 100 / Expected Sale")

    _SPECIAL_SUM_AGGREGATES = {f"{name}:sum" for name in (
        'turnover', 'sale_avg_price', 'sale_num_invoiced', 'purchase_num_invoiced',
        'sales_gap', 'purchase_gap', 'total_cost', 'sale_expected', 'normal_cost',
        'total_margin', 'expected_margin', 'total_margin_rate', 'expected_margin_rate',
    )}

    def _read_group_select(self, aggregate_spec, query):
        # the purpose of this override is to flag the aggregates above as such:
        # field._description_aggregator() should simply not fail
        if aggregate_spec in self._SPECIAL_SUM_AGGREGATES:
            return SQL()
        return super()._read_group_select(aggregate_spec, query)

    @api.model
    def _read_group(self, domain, groupby=(), aggregates=(), having=(), offset=0, limit=None, order=None):
        """
            Inherit _read_group to calculate the sum of the non-stored fields, as it is not automatically done anymore through the XML.
        """
        if self._SPECIAL_SUM_AGGREGATES.isdisjoint(aggregates):
            return super()._read_group(domain, groupby, aggregates, having, offset, limit, order)

        base_aggregates = [*(agg for agg in aggregates if agg not in self._SPECIAL_SUM_AGGREGATES), 'id:recordset']
        base_result = super()._read_group(domain, groupby, base_aggregates, having, offset, limit, order)

        # Force the compute of all records to bypass the limit compute batching (PREFETCH_MAX)
        all_records = self.browse().union(*(item[-1] for item in base_result))
        # This line will compute all fields having _compute_product_margin_fields_values
        # as compute method.
        self._fields['turnover'].compute_value(all_records)

        # base_result = [(a1, b1, records), (a2, b2, records), ...]
        result = []
        for *other, records in base_result:
            for index, spec in enumerate(itertools.chain(groupby, aggregates)):
                if spec in self._SPECIAL_SUM_AGGREGATES:
                    field_name = spec.split(':')[0]
                    other.insert(index, sum(records.mapped(field_name)))
            result.append(tuple(other))

        return result

    def _compute_product_margin_fields_values(self):
        if not self.ids:
            for field_name, field in self._fields.items():
                if field.compute == '_compute_product_margin_fields_values':
                    self[field_name] = False
            return

        date_from = self.env.context.get('date_from', time.strftime('%Y-01-01'))
        date_to = self.env.context.get('date_to', time.strftime('%Y-12-31'))
        invoice_state = self.env.context.get('invoice_state', 'open_paid')
        res = {
            product_id: {'date_from': date_from, 'date_to': date_to, 'invoice_state': invoice_state, 'turnover': 0.0,
                'sale_avg_price': 0.0, 'purchase_avg_price': 0.0, 'sale_num_invoiced': 0.0, 'purchase_num_invoiced': 0.0,
                'sales_gap': 0.0, 'purchase_gap': 0.0, 'total_cost': 0.0, 'sale_expected': 0.0, 'normal_cost': 0.0, 'total_margin': 0.0,
                'expected_margin': 0.0, 'total_margin_rate': 0.0, 'expected_margin_rate': 0.0}
            for product_id in self.ids
        }
        states = ()
        payment_states = ()
        if invoice_state == 'paid':
            states = ('posted',)
            payment_states = ('in_payment', 'paid', 'reversed')
        elif invoice_state == 'open_paid':
            states = ('posted',)
            payment_states = ('not_paid', 'in_payment', 'paid', 'reversed', 'partial')
        elif invoice_state == 'draft_open_paid':
            states = ('posted', 'draft')
            payment_states = ('not_paid', 'in_payment', 'paid', 'reversed', 'partial')
        if "force_company" in self.env.context:
            company_id = self.env.context['force_company']
        else:
            company_id = self.env.company.id
        self.env['account.move.line'].flush_model(['price_unit', 'quantity', 'balance', 'product_id', 'display_type'])
        self.env['account.move'].flush_model(['state', 'payment_state', 'move_type', 'invoice_date', 'company_id'])
        self.env['product.template'].flush_model(['list_price'])
        sqlstr = """
                WITH currency_rate AS MATERIALIZED ({})
                SELECT
                    l.product_id as product_id,
                    SUM(
                        l.price_unit / (CASE COALESCE(cr.rate, 0) WHEN 0 THEN 1.0 ELSE cr.rate END) *
                        l.quantity * (CASE WHEN i.move_type IN ('out_invoice', 'in_invoice') THEN 1 ELSE -1 END) * ((100 - l.discount) * 0.01)
                    ) / NULLIF(SUM(l.quantity * (CASE WHEN i.move_type IN ('out_invoice', 'in_invoice') THEN 1 ELSE -1 END)), 0) AS avg_unit_price,
                    SUM(l.quantity * (CASE WHEN i.move_type IN ('out_invoice', 'in_invoice') THEN 1 ELSE -1 END)) AS num_qty,
                    SUM(CASE WHEN i.move_type = 'out_invoice' THEN -l.balance WHEN i.move_type = 'in_invoice' THEN l.balance ELSE -ABS(l.balance) END) AS total,
                    SUM(l.quantity * pt.list_price * (CASE WHEN i.move_type IN ('out_invoice', 'in_invoice') THEN 1 ELSE -1 END)) AS sale_expected
                FROM account_move_line l
                LEFT JOIN account_move i ON (l.move_id = i.id)
                LEFT JOIN product_product product ON (product.id=l.product_id)
                LEFT JOIN product_template pt ON (pt.id = product.product_tmpl_id)
                left join currency_rate cr on
                (cr.currency_id = i.currency_id and
                 cr.company_id = i.company_id and
                 cr.date_start <= COALESCE(i.invoice_date, NOW()) and
                 (cr.date_end IS NULL OR cr.date_end > COALESCE(i.invoice_date, NOW())))
                WHERE l.product_id IN %s
                AND i.state IN %s
                AND i.payment_state IN %s
                AND i.move_type IN %s
                AND i.invoice_date BETWEEN %s AND  %s
                AND i.company_id = %s
                AND l.display_type = 'product'
                GROUP BY l.product_id
                """.format(self.env['res.currency']._select_companies_rates())
        invoice_types = ('out_invoice', 'out_refund')
        self.env.cr.execute(sqlstr, (tuple(self.ids), states, payment_states, invoice_types, date_from, date_to, company_id))
        for product_id, avg, qty, total, sale in self.env.cr.fetchall():
            res[product_id]['sale_avg_price'] = avg and avg or 0.0
            res[product_id]['sale_num_invoiced'] = qty and qty or 0.0
            res[product_id]['turnover'] = total and total or 0.0
            res[product_id]['sale_expected'] = sale and sale or 0.0
            res[product_id]['sales_gap'] = res[product_id]['sale_expected'] - res[product_id]['turnover']
            res[product_id]['total_margin'] = res[product_id]['turnover']
            res[product_id]['expected_margin'] = res[product_id]['sale_expected']
            res[product_id]['total_margin_rate'] = res[product_id]['turnover'] and res[product_id]['total_margin'] * 100 / res[product_id]['turnover'] or 0.0
            res[product_id]['expected_margin_rate'] = res[product_id]['sale_expected'] and res[product_id]['expected_margin'] * 100 / res[product_id]['sale_expected'] or 0.0

        ctx = self.env.context.copy()
        ctx['force_company'] = company_id
        invoice_types = ('in_invoice', 'in_refund')
        self.env.cr.execute(sqlstr, (tuple(self.ids), states, payment_states, invoice_types, date_from, date_to, company_id))
        for product_id, avg, qty, total, _dummy in self.env.cr.fetchall():
            res[product_id]['purchase_avg_price'] = avg and avg or 0.0
            res[product_id]['purchase_num_invoiced'] = qty and qty or 0.0
            res[product_id]['total_cost'] = total and total or 0.0
            res[product_id]['total_margin'] = res[product_id].get('turnover', 0.0) - res[product_id]['total_cost']
            res[product_id]['total_margin_rate'] = res[product_id].get('turnover', 0.0) and res[product_id]['total_margin'] * 100 / res[product_id].get('turnover', 0.0) or 0.0
        for product in self:
            res[product.id]['normal_cost'] = product.standard_price * res[product.id]['purchase_num_invoiced']
            res[product.id]['purchase_gap'] = res[product.id]['normal_cost'] - res[product.id]['total_cost']
            res[product.id]['expected_margin'] = res[product.id].get('sale_expected', 0.0) - res[product.id]['normal_cost']
            res[product.id]['expected_margin_rate'] = res[product.id].get('sale_expected', 0.0) and res[product.id]['expected_margin'] * 100 / res[product.id].get('sale_expected', 0.0) or 0.0
            product.update(res[product.id])
        return res
